Energy Outputs and Financial Returns of On-Farm Biodigester Systems in the United States: A Case Study in Vermont

This study assesses the investments, energy outputs, and financial returns of on-farm anaerobic digester systems (ADS) by farm size through a case study in Vermont and discusses the potential policy implications. Detailed data on the initial investments, production of electricity and other marketable products, operational expenses, and income, collected through surveys of eight operating ADS on dairy farms in Vermont, are used to estimate the return on equity (ROE), return on assets (ROA), and other financial indicators for small, medium, and large farms. The primary survey data indicate that the average investment was $1.35 million for small and medium farms (75-500 cows) and $2.44 million for large farms (>500 cows). Financial analysis indicates that the ROE and ROA were 12.54% and 13.50% for large farms but only 0.73% and 1.07% for small and medium dairy farms, respectively. Whereas the technology of ADS developed in the United States seems to favor large farms in terms of both energy production and financial returns, the centralized ADS developed in Europe and low-cost mini digesters developed in China may have potentials for small and medium farms to develop more economically viable ADS in the United States.